Cesare Prandelli has described Mario Balotelli as the man to take Italy “to the moon” with one performance and crash down to earth with the next, as the manager reinforced the need for high-end consistency from the striker.

Balotelli was the matchwinner for Italy in their opening Group D match against England, his header giving them a 2-1 victory, and his overall performance delighted the manager. But, before Friday’s game against Costa Rica, Prandelli warned that any drop in Balotelli’s levels would see the player replaced.

“If we look at the four years that we have had with Mario there have been times when he has been our weapon, he was the asset, he was the man who would have taken us to the moon,” Prandelli said. “But then, after two months, he wasn’t performing. Many thought that he would not even make it to the World Cup so what really matters is that he concentrated and he is focused.

“It’s important for him to do what he did in the last match, to be as intense. If he can do that for 90 minutes, great. Otherwise we will have someone just as good and just as fresh in the pitch. We started with 23 men and he is one of those 23 men. He may be decisive, he may be important but, as in the last match, he must give 100%.”

Balotelli mixed the sublime with the ridiculous for Milan during the past domestic season and he is one of only two out-and-out strikers in Prandelli’s squad. Ciro Immobile, who led the Serie A scoring charts with 22 goals for Torino and has since transferred to Borussia Dortmund, is the other.

Balotelli sat alongside Prandelli in the pre-match press conference and he appeared determined to say little and reveal nothing. The 23-year-old has been linked with a possible move to Arsenal but he is “concentrated 100% on the World Cup. What comes later, we shall see. I know nothing”.

He was asked about his pre-World Cup proposal to his girlfriend, Fanny Neguesha. “That had nothing to do with the World Cup,” he replied. “I would have proposed anyway.” What about his position in Italy’s formation as the lone striker? “I don’t mind as long as I play,” he said.

He went on to declare that he was not interested in the possibility of the Ballon d’Or as the team was the only thing that mattered. Even Geoffrey Boycott did not have as straight a bat.

“I’m experiencing this moment with great peace of mind,” Balotelli said. “I don’t feel any pressure. I am tranquil. I’d like to go as far as possible at this World Cup and I hope to score as many as I can but the important thing is for the team to win and proceed. I hope it’s not Mario’s World Cup but Italy’s World Cup. I don’t want to be the great star.”

It was left to Prandelli to discuss his concerns about the heat in Recife for the 1pm kick-off local time and his theories about why South American teams had impressed so far at the tournament.

“As far as I’m concerned, the South American teams have an advantage, and not just because they live and operate under these conditions,” Prandelli said. “It is because their explosiveness is different to that of the European teams. Based on the data and the matches we have analysed, the Europeans withstand more, they are more resilient but they are less explosive in the sprint.

“As for the climate, it can change very quickly. At 1.20pm or 1.25pm, it was 29C and with 57% humidity. Twenty minutes later, the clouds disappeared and we almost had 40C and 70% humidity. I always think there should be water time-outs.”

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